There are now several satellites in relatively close proximity to each other (when seen from the ground) transmitting television at the same or similar frequencies to one another. Many satellite receiver systems comprise a fixed antenna which is aligned with a single satellite to receive television signals therefrom. The close proximity of several satellites all transmitting at the same or similar frequencies makes it difficult to align an antenna with the correct satellite during installation. Using only a signal strength meter it is all too easy for an taller mistakenly to align the antenna with a nearby satellite transmitting at the same frequency as the correct satellite. Identifying and correcting such an error is relatively straightforward: when decoded and viewed on a television screen it will be immediately apparent that the wrong signal is being received. However, relying on viewing the picture is time consuming and therefore undesirable.
The present invention aims to facilitate installation of a satellite system by improving the confidence of the correct signal being received.
In one aspect the invention provides an antenna alignment meter comprising a signal detector circuit for detecting a signal with predetermined characteristics and outputting data pertaining to the detection of the signal; a connector for connecting the signal detector circuit to an antenna; and a controller responsive to the data from the detector circuit for controlling generation of an indicator that the signal has been detected.
In another aspect the invention provides a method of aligning an antenna with a signal source, the method comprising: connecting the antenna to an antenna alignment meter; adjusting the orientation of the antenna until the antenna alignment meter indicates detection of a signal with predetermined characteristics; and locking the antenna in position.
The invention also provides an apparatus for aligning an antenna with a signal source, the apparatus being arranged to monitor signals received by the antenna and to provide an indication of correct alignment of the antenna with a desired signal source when a signal of a predetermined frequency, polarization, symbol rate and error correction ratio is received.